I have one and agree with Tom. I used mine a lot with a Manfrotto 488 ballhead when I first got it but much less now that I have a tripod that will get down nice and low. It is good for car window use, but even more than that it gives many options if you want to shoot from walls, down on the ground for Macro or eye level bird/wildlife shooting, even as a chest brace to make hand-held shooting more stable. It's very well constructed and a really well thought through product.
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